From the past, a plastic material has been used as an alternative to an inorganic material for the application to an optical component. Since such a plastic material can be tinted, and is lightweight and hardly broken as compared to an inorganic material which has been used, the plastic material has been suitably used. In particular, as an optical component such as a lens or the like, a plastic material having a high refractive index has been required. As such a plastic material having a high refractive index, there has been proposed a sulfur-containing urethane (thiourethane) based resin as described, for example, in Patent Documents 1 and 2.
Patent Document 1: Japanese Patent Laid-open No. 1990-270859
Patent Document 2: Chinese Patent Laid-open No. 1405198